Naturally Pure®
SPA
Enzyme Cleaner & Phosphate Remover contains proprietary mineral (Not lanthanum,
as found in other cheaper products) that when added to your spa creates a thin film on your
spa's filter which then physically removes phosphates (especially ortho-phosphates
- the kind typically found in swimming pools & spas) from the water.

Phosphates can further "fuel" bacterial growths & therefore
worsen a
biofilm problem. Phosphates can also combine with minerals such as calcium
forming a calcium phosphate complex, which leads to scale formation, waterline
build-up that is difficult to remove & dull water.

In salt-water hot tubs (ParPools.com does not recommend salt
in spas & hot tub tubs), phosphate can coat the electrodes (scale) of the
chlorine generator, preventing efficient production of chlorine.